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The classic example of a dehydration reaction is the Fischer esterification, which involves treating a carboxylic acid with an alcohol to give an ester RCO 2 H + R′OH ⇌ RCO 2 R′ + H 2 O. Often such reactions require the presence of a dehydrating agent, i.e. a substance that reacts with water.
Ammonia solution, also known as ammonia water, ammonium hydroxide, ammoniacal liquor, ammonia liquor, aqua ammonia, aqueous ammonia, or (inaccurately) ammonia, is a solution of ammonia in water. It can be denoted by the symbols NH 3 (aq). Although the name ammonium hydroxide suggests a salt with the composition [NH + 4][OH −
An ester of carboxylic acid.R stands for any group (organic or inorganic) and R′ stands for organyl group.. In chemistry, an ester is a compound derived from an acid (organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group (−OH) of that acid is replaced by an organyl group (−R).
Alkaline hydrolysis of esters is also known as saponification. A base such as sodium hydroxide is required in stochiometric amounts. Unlike acid-catalyzed ester hydrolysis, it is not an equilibrium reaction and proceeds to completion. Hydroxide ion attacks the carbonyl carbon to give a tetrahedral intermediate, which then expels an alkoxide ion.
The synthetic procedure [16] is typical for this type of reaction. In the process, in addition to water, an equivalent of ethanol and carbon dioxide are lost in decarboxylation. Ethyl glyoxylate 2 and glutaconate (diethyl-2-methylpent-2-enedioate) 1 react to isoprenetricarboxylic acid 3 (isoprene (2-methylbuta-1,3-diene) skeleton) with sodium ...
The reaction is often carried out without a solvent (particularly when a large reagent excess of the alcohol reagent is used) or in a non-polar solvent (e.g. toluene, hexane) that can facilitate Dean–Stark distillation to remove the water byproduct. [4] Typical reaction times vary from 1–10 hours at temperatures of 60–110 °C.
Carbamic acid is a planar molecule. [3]The H 2 N− group of carbamic acid, unlike that of most amines, cannot be protonated to an ammonium group H 3 N + −.The zwitterionic form H 3 N + −COO − is very unstable and promptly decomposes into ammonia and carbon dioxide, [6] yet there is a report of its detection in ices irradiated with high-energy protons.
Ethyl sulfate can be produced in a laboratory setting by reacting ethanol with sulfuric acid under a gentle boil, while keeping the reaction below 140 °C. The sulfuric acid must be added dropwise or the reaction must be actively cooled because the reaction itself is highly exothermic. CH 3 CH 2 OH + H 2 SO 4 → CH 3 CH 2 OSO 3 H + H 2 O